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COVID-19 is a respiratory illness. So why do so many patients who have it lose weight?

A study in the October 2020 issue of the medical journal Clinical Nutrition looked at 213 patients who contracted the coronavirus, nearly three-quarters of whom had illness so severe that they were hospitalized. Of the patients, 70 percent were overweight or obese and 29 percent lost greater than 5 percent of their initial body weight during their illness.

The weight loss makes sense when you consider patients’ symptoms:

• COVID-19 causes alterations of smell and taste, fatigue and loss of appetite, all of which can affect food intake.
• Patients who feel ill typically are immobilized and confined either at home or in the hospital, which means they’re not exercising or using their muscles, which quickly experience loss without use.
• The virus itself makes for labored breathing.

“Many COVID-19 patients are in a hypermetabolic situation, meaning that it takes a lot of energy to breathe,” explains Matthew Yotsuya, M.D., an internist at Raritan Bay Medical Center in Perth Amboy, New Jersey. “People who have COVID-19 spend a tremendous amount of energy just trying to keep themselves oxygenated. Because of that, people tend to lose a lot of weight.”

More Concerning Than Weight Loss

For Dr. Yotsuya, what’s more concerning than COVID-related weight loss is pre-COVID weight gain, which makes patients more vulnerable to the virus in the first place. “Independent of most other risk factors, people who are obese—even if they don’t have hypertension, diabetes or other medical issues from their obesity—have a greater risk of mortality from COVID-19,” Dr. Yotsuya continues. “We don’t really understand why that is. But even among people in their 30s and 40s, we’ve seen relatively healthy patients who are just a little bit overweight—with a BMI of 30, for example—get really, really sick or die.”

Although doctors don’t yet understand the relationship between the coronavirus and obesity, what they know for certain is this, according to Dr. Yotsuya: Maintaining a healthy weight through diet and exercise is one of the most effective things individuals can do to protect themselves from illness— including not only the known illnesses of today, but also the new illnesses of tomorrow.

Next Steps & Resources:

• Meet our source: Matthew Yotsuya, M.D.
• To make an appointment with Dr. Yotsuya, call 800-822-8905 or visit our website.
  
  The material provided through HealthU is intended to be used as general information only and should not replace the advice of your physician. Always consult your physician for individual care.